The invention relates to a method for providing traffic status information, a system for transmitting traffic status information, a device in a vehicle for generating and sending traffic status information and a computer program product for use in a motor vehicle and for generating and sending traffic status information.
Known vehicles send so-called “floating car data” (FCD). The system used for this purpose consists of a GPS receiver and a GSM module. Both modules are already present in many vehicles even without FCD functionality. The GPS receiver measures the position and the FCD methods determine the travel times of the vehicle from a multitude of such position data. These travel times are sent like a string of beads (individual points on the trip route with position coordinates and equipped with a time stamp) to central traffic information offices via a GSM network. These offices can draw inferences regarding the traffic situation from these travel times. This allows data acquisition of traffic status information for traffic information services.
Data transmission via the GSM network is associated with a high cost.
In the future, FCD will be developed into XFCD (extended floating car data) to make the acquisition of traffic position data more accurate and also to provide information about the weather, road condition and local hazards. XFCD uses the various sensors and subsystems present in the vehicle, which are already making their data available on central data buses in the vehicle. Analysis of the various data en route can provide information about traffic conditions, impaired visual conditions, road conditions (roadway surfaces), infrastructural conditions (winding roads), local hazards, rainfall, slippery road conditions and skidding hazards.
The object of this invention is in particular a method for providing high quality traffic status information at an acceptable cost.
An aspect of the inventive method for providing traffic status information as part of the traffic status detection by a traffic status detection device provided in the motor vehicle consists of performing the following steps. According to this invention, the traffic status information is used in particular for detecting traffic situations, such as for detecting congested traffic. In a first step, a traffic status is detected repeatedly by the traffic status detection device, and in a second step, a change in traffic status is ascertained, i.e., detected, by the traffic status detection device. In a third step, a data record describing the change in traffic status is generated by the traffic status detection device, in particular a program-controlled computer, and finally in a fourth step, the data record is transmitted from the traffic status detection device to a receiver that receives the data record. This may be accomplished via Short Message Service (SMS), for example.
Through this method, in particular for providing traffic status information for the acquisition of traffic situations in the entire highway network, it is possible to largely reliably detect a traffic event and/or a change in traffic status such as a change from a “driving freely” traffic status to a “congested” traffic status and to transmit the traffic event as a given condition only when it in fact occurs, i.e., the inventive method permits an event-oriented generation of traffic status information. Traffic status information is transmitted only when prompted by the traffic status detected, e.g., congested traffic. Event-oriented data transmission to an institution that reconstructs and reports the traffic situation, in particular a central traffic information office, is currently performed via SMS, but this limits the data transmission required to display the traffic situation to a minimum. This means considerable cost savings without impairing the quality of the traffic situation detection.
Instead, the inventive method for the first time permits an inexpensive and nevertheless almost real time data acquisition for the entire roadway system, in particular on highways, country roads and city roads.
In one embodiment of the present invention, the data record indicates whether a change in traffic status from the traffic of “congestion” to the traffic status “driving freely” (510) or a change in traffic status from the traffic status of “driving freely” to the traffic status of “congestion” has been detected by the traffic status detection device provided in the motor vehicle.
Alternatively or additionally, in one embodiment of this invention, in ascertaining the traffic states of “congestion” or “driving freely” a check is performed several times to determine whether the relevant speed of the vehicle is less than a lower speed threshold and greater than an upper speed threshold.
Alternatively or additionally, in another embodiment of this invention, the check is performed periodically and the traffic status of “congestion” or “driving freely” considered as prevailing is the state that has been occurring largely without interruption and was the first to do so with a predetermined frequency.
Through the continuous detection of the two states and not only a single state, it is possible to detect reliably whether there is congested traffic and also to detect reliably whether uncongested continuation of driving is possible again. This avoids rapid and unreliable switching back and forth between the two states of “congestion” and “driving freely” on the basis of merely short-term changes in the traffic situation.
Alternatively or additionally, in another embodiment of this invention the data record describing the change in traffic status also indicates the place and time of the change in traffic status, in particular the beginning or end of the congested traffic.
Through the measures mentioned above, a precise and current determination of the traffic situation is made possible, such as a detection of congestion. Unnecessary detours because of congested traffic which is merely presumed to exist can thus be avoided throughout the entire traffic network—and not only on the highways.
Alternatively or additionally, in one embodiment of the invention, after transmission of the data record of the change in traffic status after a predetermined interval of time and/or distance, a second data record describing the traffic status, in particular the congested traffic, is transmitted by the vehicle. This second data record indicates in particular the average speed in the congested traffic and/or frequency of stopping in the preceding interval.
This measure makes it possible to automatically provide an updated traffic situation report after an initial change in traffic status and before a second change in traffic status. Furthermore, the second data record allows a more precise determination of the change in traffic status in time or space.
Alternatively or additionally, in one embodiment of the invention, the receiver is a central traffic information office, which may be a regional central traffic information office which supplies a traffic situation report using the data record.
Alternatively or additionally, in one embodiment of the invention, the traffic situation is made available using the data record and other traffic status information, in particular information from local measurement points such as induction loops, bridge sensors, camera systems, signal lights or mobile measurement sites, such as reporting vehicles, traffic jam reporters or police reports. This linking of traffic status information from different sources permits a precise determination of the traffic situation which largely covers the area. In the case of regional central traffic information offices, they are better able to take into account regional requirements than would be possible with a single central office.
Alternatively or additionally, in one embodiment of the invention, the receiver is at least one other vehicle that analyzes the data record to support the driver and/or relays the data record to other vehicles and/or to central traffic information offices via data collecting points, in particular relaying the information to a transmission network via a wireless interface. This measure makes it possible for vehicles to mutually transmit relevant traffic status information, optionally including a central traffic information office, in particular for determining the traffic situation.
The inventive method for acquiring data also permits an advantageous system for transmitting traffic status information from a first vehicle to a second vehicle, in particular via an ad hoc network or from a central traffic information office to one or more vehicles, optionally modified, in particular by broadcast. It is likewise possible for an advantageous device and a computer program product to be used in a motor vehicle for generating and transmitting traffic status information.
Other objects, advantages and novel features of the present invention will become apparent from the following detailed description of the invention when considered in conjunction with the accompanying drawings.